1997 5.7L thunderbolt ignition. Slow crank

[findinghomer]

If you can’t turn the engine by hand, I’d also be leaning toward something mechanical. The voltage drop could just be the starter pulling hard against a locked engine. Since the cables worked fine the day before, I’d check the simple things first (starter, connections, possible hydraulic lock), but if those check out, internal damage seems likely.

Okay thanks for corroborating, that was the only thing I was unsure of is if that voltage drop could be because the starter is drawing so much power against a seizing engine. I've been slowly getting it apart just kind of taking tips as I go lol

 

[cwella]

Makes sense. Hopefully you find the cause as you keep tearing it down. Taking it slow and checking things along the way is the best way to go. Keep us updated!

 

[DeepCMark58A]

Do you have access to a ground meter? I would borrow mine but it is a $1500 meter and company property. That would diagnose the ground issue in a second.

 

[findinghomer]

Do you have access to a ground meter? I would borrow mine but it is a $1500 meter and company property. That would diagnose the ground issue in a second.

I don't, But I've moved on from thinking it's an electrical problem because I can't turn the engine by hand.

 

[nola mike]

I don't, But I've moved on from thinking it's an electrical problem because I can't turn the engine by hand.

How have you tried to turn it? Are you moving it a teeny tiny bit or are you actually doing it correctly? I'm thinking the former because of the whole "valves aren't moving" comment. 2 rotations of the engine and you would have seen everything moving. Have you checked the oil? Did you disconnect belts? A subtle catastrophic engine failure after running on muffs (turned over fine, 10 minutes later is locked) doesn't seem particularly likely, but you seem hell bent on replacing the engine at this point. Ultimate parts cannon.

 

[findinghomer]

How have you tried to turn it? Are you moving it a teeny tiny bit or are you actually doing it correctly? I'm thinking the former because of the whole "valves aren't moving" comment. 2 rotations of the engine and you would have seen everything moving. Have you checked the oil? Did you disconnect belts? A subtle catastrophic engine failure after running on muffs (turned over fine, 10 minutes later is locked) doesn't seem particularly likely, but you seem hell bent on replacing the engine at this point. Ultimate parts cannon.

I mean I really don't want to replace the engine by any means, I'd rather not lol But yes I tried to turn it by hand on that 16 mm bolt on the harmonic balancer, it doesn't budge not even a little bit. And from my understanding I shouldn't have to turn it hard enough to the point where it will break, and that's about how hard I'm turning it I'm afraid I'll break it. I did take the drive belt off and check the oil. I have the valve covers off like you suggested, (ignore the whole valve sticking thing I was mistaking they were just opened up because of the position they were in when I turned the key off) I have never torn into an engine before so I didn't know what to be looking for. But other than that , the starboard side I found a couple rockers arms that had rust deposit on it. But both sides look pretty well lubricated and clean but I don't really know what is considered good or clean. So I've just been slowly taking it apart As I check back for any input. It's hot outside so I just work for about 15 or 20 minutes and then come in and do some more research on all of this. Got the riser and spacer and exhaust pipes out going to get the starboard manifold off and then try to see how the starboard side head comes off

 

[cwella]

I mean I really don't want to replace the engine by any means, I'd rather not lol But yes I tried to turn it by hand on that 16 mm bolt on the harmonic balancer, it doesn't budge not even a little bit. And from my understanding I shouldn't have to turn it hard enough to the point where it will break, and that's about how hard I'm turning it I'm afraid I'll break it. I did take the drive belt off and check the oil. I have the valve covers off like you suggested, (ignore the whole valve sticking thing I was mistaking they were just opened up because of the position they were in when I turned the key off) I have never torn into an engine before so I didn't know what to be looking for. But other than that , the starboard side I found a couple rockers arms that had rust deposit on it. But both sides look pretty well lubricated and clean but I don't really know what is considered good or clean. So I've just been slowly taking it apart As I check back for any input. It's hot outside so I just work for about 15 or 20 minutes and then come in and do some more research on all of this. Got the riser and spacer and exhaust pipes out going to get the starboard manifold off and then try to see how the starboard side head comes off

You’re doing the right thing by not forcing it. If the crank won’t turn by hand, don’t keep leaning on it as you could damage something.

Since you have the manifolds off, check the cylinders through the spark plug holes for rust, water, or any signs of a stuck piston. The rust on the rocker arms is worth watching, as it may point to moisture getting into that side.

Take your time, keep taking pictures, and inspect before pulling everything apart. You’re approaching it the right way.

 

[findinghomer]

How have you tried to turn it? Are you moving it a teeny tiny bit or are you actually doing it correctly? I'm thinking the former because of the whole "valves aren't moving" comment. 2 rotations of the engine and you would have seen everything moving.

Oh and when I crank it with the key and look at the engine with the covers off, I can see all of the valves moving they're not stuck. But it just doesn't move when I crank it by hand. Also the only reason I've been kind of optimistic about it not being internal damage is I find it hard to believe it just subtly had catastrophic failure myself but I just don't see what else it could be if the engine won't turn.

 

[findinghomer]

You’re doing the right thing by not forcing it. If the crank won’t turn by hand, don’t keep leaning on it as you could damage something.

Since you have the manifolds off, check the cylinders through the spark plug holes for rust, water, or any signs of a stuck piston. The rust on the rocker arms is worth watching, as it may point to moisture getting into that side.

Take your time, keep taking pictures, and inspect before pulling everything apart. You’re approaching it the right way.

Thanks. I don't have the manifolds off yet but I plan on having one of them off in the next hour. I'm cooling down now it's pretty hot the boat's in the middle of the Sun . But once I get the starboard side manifold off taking the head off is where I'm entering new territory never done that before so before I do anything I'm going to do a lot of reading and or reach out if any of you guys are around . Thanks alot

 

[alldodge]

To take head off
disconnect everything attached to intake manifold and carb (cables, wires, fuel line), aqlso any brackets attached to hed

remove all intake bolts and lift it off, may need to pry slightly if gasket is hanging

loosen rockers and mark push rods. Use a cardboard box and make small holes one for each rod

remove head bolts and lift head off

 

[findinghomer]

To take head off
disconnect everything attached to intake manifold and carb (cables, wires, fuel line), aqlso any brackets attached to hed

remove all intake bolts and lift it off, may need to pry slightly if gasket is hanging

loosen rockers and mark push rods. Use a cardboard box and make small holes one for each rod

remove head bolts and lift head off

Okay, And these are all the head bolts, I think I counted nine of them?

Also when you say loosen the rockers , I don't remove the bolt completely just loosen them? And when am I marking the push rod, what exactly do you mean by that? Also I was watching one guy take a head off, and it sounded like A bunch of metal stuff fell out when he pulled it out. Is that normal?

 

[alldodge]

Okay, And these are all the head bolts, I think I counted nine of them?

Yes, ones under the cover and shorter ones no the outside edge

Also when you say loosen the rockers , I don't remove the bolt completely just loosen them? And when am I marking the push rod, what exactly do you mean by that? Also I was watching one guy take a head off, and it sounded like A bunch of metal stuff fell out when he pulled it out. Is that normal?

Loosen the nut just enough to remove the push rod. Take a card board box mark the front of the head and the side working on. Number the rods on the box, push the rods removed partly into the box next to the number they correspond to to where they were removed from the head

 

[findinghomer]

Yes, ones under the cover and shorter ones no the outside edge


Loosen the nut just enough to remove the push rod. Take a card board box mark the front of the head and the side working on. Number the rods on the box, push the rods removed partly into the box next to the number they correspond to to where they were removed from the head

Okay thx ! When I get it off I'll send you a picture, if it's catastrophic I guess it won't matter where the rods go I'll be putting a new engine in it lol

 

[alldodge]

Yes, it won't matter if your getting another motor